Loops vs Mailchimp

Contact model: a property bag versus an audience

In Loops every contact is a row with eight built-in properties and whatever custom ones you add. The contact properties documentation lists string, number, boolean and date types, reserves names such as id and teamId, and warns that a property cannot be edited once it exists. The User ID property is the one to use if your product has its own customer identifier, because Loops needs it before you can change a contact's email address through the API. Subscribed is a property too, and setting it to true through the API will re-subscribe someone who opted out, which is easy to do by accident in a nightly sync.

Mailchimp's model, described in Getting Started with Your Audience, starts from an audience that holds subscribed, unsubscribed and non-subscribed contacts. Mailchimp's advice is to keep one primary audience and organise people with tags, groups and segments. The import guide adds that separate audiences are independent, so duplicates and opt-outs are not detected across them. For a SaaS that is the main thing to avoid: do not create one audience for trial users and another for customers.

• Both tools lack an account or company object. A B2B team stores the company name or ID on the contact and segments on it.
• Loops keeps one User Group value per contact and the Loops docs describe it as free text, so use a custom property if people belong to several groups.

Events, workflows and billing triggers

A Loops event needs an email or userId and an event name, and it creates the contact if none exists. The events documentation says you can add event properties for the email's content, add the contact to mailing lists in the same call, and test safely by sending to @example.com or @test.com addresses. In the workflow builder, an Event received trigger can start a sequence of emails, timers, audience filters, branches and experiments; the docs name signUp, canceled and activated as typical events.

For billing, the Loops Stripe integration accepts a fixed list of Stripe events that includes invoice.payment_failed, invoice.upcoming, customer.subscription.trial_will_end and customer.subscription.deleted, and syncs the customer's email and name to the Loops contact. That is a quick route to a trial-ending sequence or a failed-payment notice without writing webhook code. Stripe events outside that list are ignored.

Mailchimp's automation overview frames automations around signups, purchases and engagement, with the Free plan limited to a single email automation and full customer-journey workflows on Standard and Premium. It does not describe an endpoint equivalent to Loops' send-event call, so check the Marketing API reference to see whether your product events can enter a journey, or plan to set tags from your backend and trigger on tag changes.

Transactional email and CRM logging

Loops treats system mail as a feature of every paid plan. Per its transactional guide, you build the email in the editor or upload MJML, publish it, and call the API with the transactional ID and your data variables. Recipients do not have to be in your audience and are not counted toward billing, unsubscribed contacts still receive these emails, and a send fails if a required data variable is missing. Transactional emails carry no unsubscribe link and do not track opens or clicks, which is why Loops asks you not to put marketing content in them.

Mailchimp's transactional page explains that Mandrill was renamed Mailchimp Transactional in fall 2025, adds SMS to the same API, and lets marketers edit templates without a developer. It shows no price. Treat it as a second vendor-relationship inside the same account.

For CRM visibility, Loops offers Auto BCC: you paste your CRM's BCC address into the sending settings and every campaign and workflow email is logged there; the page names Salesforce, HubSpot and Attio. That logs mail, it does not map fields back and forth. Mailchimp lists Salesforce as one of the six apps its importer can pull contacts from.

API limits and developer effort

Loops documents its API at loops.so/docs/api-reference: a base URL of app.loops.so/api, a baseline of 10 requests per second per team, and a lower limit of 60 requests per 60 seconds on the content endpoints for campaigns, email messages, themes and transactional emails. The same API manages contacts, sends events and creates workflows, so one integration can cover everything your backend needs.

Mailchimp splits the surface in two: the Marketing API for audiences and campaigns, and the Transactional API for system mail, each with its own quick start. Two APIs means two sets of credentials and two places to monitor, which matters if a single engineer owns the integration.

Cost at 5,000, 10,000 and 25,000 contacts over two years

At about 5,000 contacts, Loops is $48 a month (the 4,788-subscriber reading), or 12 x $48 = $576 a year. Mailchimp Standard is $100 a month at list, or $1,200 a year, and $50 a month ($600) in the offer year. Over two years Loops totals $48 x 24 = $1,152 and Mailchimp totals $600 + $1,200 = $1,800. In year one the two are within $24 of each other.

At about 10,000 contacts, Loops is $99 a month (9,998 subscribers), $1,188 a year. Mailchimp Standard is $135 a month, $1,620 a year, or $67.50 a month ($810) in the offer year. Mailchimp is $378 cheaper in year one ($1,188 - $810). Over two years Loops totals $99 x 24 = $2,376 and Mailchimp $810 + $1,620 = $2,430, a $54 difference that favours Loops. So at this size the decision turns on the first year only if you are certain to leave by month 12.

At about 25,000 contacts, Loops is $198 a month (24,339 subscribers), $2,376 a year. Mailchimp Standard is $310 a month, $3,720 a year, or $155 a month ($1,860) in the offer year. Over two years Loops totals $198 x 24 = $4,752 and Mailchimp $1,860 + $3,720 = $5,580. Loops saves $828 over two years and $1,344 a year once Mailchimp's full price starts ($3,720 - $2,376).

Send volume is the second variable. If 10,000 contacts each receive 15 emails a month (150,000 sends), Mailchimp Standard's allowance of 12 x 10,000 = 120,000 is exceeded and overage charges apply; Mailchimp's additional charges article describes how they are billed. Loops has no monthly send cap on a paid plan, so the same program stays at $99.

For a list under 1,000 people, the comparison is no contest: 800 contacts receiving four emails is 3,200 sends, inside the Loops free allowance of 4,000 in any rolling 30 days. Mailchimp Free stops at 250 contacts and 500 sends a month, so the same list needs a paid Mailchimp plan, for which the capture showed $20 a month at 500 contacts and no price for the stops between 501 and 2,500.

• All prices are from the Loops pricing page (dated slider readouts) and the Mailchimp pricing page, read on 2026-10-07.
• Mailchimp's half-price offer has its own terms; confirm eligibility with Mailchimp before you count on it.
• Loops readouts are at one subscriber count each, so your own bill depends on your exact subscribed total.

What the entry plans do not include

• Loops Free: the 1,000 newest contacts only, 4,000 sends per rolling 30 days, 10 emails per second, a Loops footer. Every feature is included, so the limits are volume and branding, not capability.
• Mailchimp Free: 250 contacts, 500 sends a month, 250 a day, one audience, sending pauses past the limit.
• Mailchimp Essentials: 3 seats, sends at 10 times contacts, basic automation flows, and custom-coded templates that can be created but not sent without an upgrade.
• Mailchimp Standard: 5 seats, sends at 12 times contacts. Premium starts at $350 a month at 500 contacts, with 15 times contacts in sends and unlimited seats.

Moving from Mailchimp to Loops

1. In Mailchimp, open Audience and export. The export guide says you can export a whole audience, a segment, a tag or a group; the result may be a ZIP of separate CSVs for subscribed, unsubscribed, non-subscribed and cleaned contacts. Only Owners and Admins can export audiences, and files stay available for 30 days. Exports do not contain open and click data.
2. Decide which Mailchimp tags and groups should become Loops mailing lists or custom properties. Create each custom property in Loops first, with the correct type; the property cannot be renamed or retyped later.
3. Prepare the CSV for the Loops importer: use Email, First Name, Last Name, User Group and Source columns, plus one column per custom property named exactly like the property. Dates must use an accepted format; timestamps are not supported in CSV.
4. Import the unsubscribed file with a Subscribed column set to false. All new contacts are marked subscribed otherwise, and a later CSV cannot re-subscribe anyone who opted out. Skip the cleaned file.
5. On the review step, leave the Trigger workflows option off for the first import, or every welcome workflow will fire for your entire existing list.
6. Rebuild each Mailchimp journey as a Loops workflow, using Event received triggers for anything your product can send. Move system mail from Mailchimp Transactional to Loops transactional emails and republish each template there.

Moving from Loops to Mailchimp

1. Download your contacts from the Loops Audience page as a CSV, including custom properties and the Subscribed column. Note your event names and properties from the Loops Events page as well, since the contact file is a list of people, not an event history.
2. Split the file by subscribed status. Mailchimp's importer loads one marketing status per run, so you will run it twice: subscribed contacts as Subscribed and opted-out contacts as Unsubscribed.
3. Check your total against the contact band you are paying for. The guide warns that an import that raises the total above the plan limit leads to additional charges.
4. Choose Audience, Add contacts, Import contacts, Upload a file. Match each column to an audience field (unmatched columns are not imported), and add tags at the tagging step to represent Loops mailing lists or User Group values.
5. Rebuild workflows as Mailchimp journeys. Event received triggers have no direct equivalent in the pages we read, so set a tag from your backend or connector and trigger on that.
6. Replace Loops transactional emails with Mailchimp Transactional or another sender, and re-create sending-domain authentication before you cut over.